Dioxane derivatives and a process for making same



Patented Jan. 2, 1945 DIOXANE DERIVATIVES AND A PROCESS FORMAKING Adolf Griin, Basel, Switzerland, assignor to J. a. Geigy A. ,G.,. Basel, Switzerland, a Swiss com- No Drawing. Application February 4, 1943, Serial No. 474,725. In Switzerland January 5, 1942 3 Claims. (01. 260-247) 1 of 2-n caustic potash lye and then stirred with 1 100 parts of glycerine-epichlorhydrine under a Among the derivatives of the arylene dioxanes only the benzo-lz l-dioxane substituted in the heteroring have become known hitherto, while derivatives thereof substituted in the aromatic nucleus in O-position to one of the 2-oxygen atoms of the dioxane ring were not yet accessible. It has now been found that these compounds are obtained by causing epihalogenhydrines to re-- act with alkalin solutions of polyvalent phenols containing two hydroxyl groups in ortho-position and at least a third substituent or an annulated ring. When working in this manner, 2-hydroxymethyl-benzodioxanes or -naphthodioxanes re spectively and the like are obtained whichare substituted in the aromatic nucleus. From these compounds further derivatives may be obtained especially by replacing the hydroxyl groups in 2-position bya halogen atom and by changing the halogen by an amino group and the like.

As substituents in the nucleus come into question: alkyl, alkoxy, carboxy, carbalkoxy, aminoalkyl or alkylamino groups. These compounds also react readily, when the same or their alkali compounds are caused, even without furnishing any heat, to react with an pihalogenhydrine,

this reaction has only been observed hitherto for the pyrocatechine (and this only when working under stronger reaction conditions) so that this reaction has been considered to a certain extent as specific for this compound. Besides, most of the o-diphenols suitably substituted and required as starting or intermediate products respectively have not yet been known. The compounds prepared according to the present invention have proved without exception to be physiologically active substances beingmore active than the analogous compounds whichare not substituted in the benzene nucleus. The suitably substituted compounds such as the hydroxyl and amino derivatives also offer the advantage that they may be further derived, e. g. acylated, which fact is often important for the gradation of the effects. The new products may be used as therapeutics or as therapeutical intermediates in the pharmaceutical-chemical industry.

This application contains subject matter. related to that disclosed in Griin application 474,874 filed February 5, 1943.

The present invention. is illustrated, but not limited, by the following examples, wherein the parts are by weight.

Example 1 feeble temporary self-heating of the mixture. The latter is shaken still for 20 hours, then the product thus precipitated from the aqueous solution is separated and the latter extracted; the

- extract is now combined" with the mainquantity, whereupon the unconsurned epichlorhydrine still present in the mixture is distilled off in a vacuo on the water-bath and regenerated. Thus 85-88 parts of 2-hydroxymethyl-o methyl-benzodioxane remain which may be obtained in a pure form as colorless liquidby distillation. Its boiling point at a pressure of 1 mm. is 129-130 C.

80 parts of this hydroxymethylcompound are mixedwith parts of pyridine, then, under coolingwith ice, 55 parts of thionylchloride are al-. 1 lowed to slowly dro thereinto and, after a long standing, the mixtur is heated on the water bath during a short time. The Whole mixture 1 is now poured into ice-water and the product possibly diluted by means of ether or of the like is decanted, freed from acid by washing with water, dried and distilled. About 75 parts of 2- chloromethyl-o-methylbenzodioxane, a viscous liquid, are obtained; boiling point at 1.3 mm. pressure. 137 C. 1

'70 parts of this chlorine derivative are heated to 150 C. for 8 hours under pressure together with 62 parts of morpholine. (Instead of the chlorine derivative 86 parts of the analogous bromin derivative may be used.) 1 Aftercooling, the liquid reaction product 'which has been diluted with ether or the lik is separated by suction from the precipitated morpholine hydrochloride and taken up into sulfuric acid 1:4. The sulfate solution is made alkalin after purification by shaking with water and the base thus precipitated, about 75 parts, combined, dried and distilled. The resultant 2-morpholinylmethyl-omethylbenzodioxaneof the formula is liquid, colorless and odorless, B. P.o.55 mm. 141 C.; 1 g. consumes 40.4 com. n/10 acid, calculated 40.1 com., for the neutralisation against methyl orange. The salts are easily soluble in water reacting acid to litmus. The hydrochloride constitutes white crystals, M. P. 200C.

guaiacol, B. R13 mm. 95 C., M. P. 455 C., which is then demethylated by heating it with concen-- trated hydrobromic acid or also with hydrochloric vanilline there is obtained in this manner the l-methyl-3z l-dihydroxybenzene and therefrom according to the above described process an isomeric methylhydroxymethyl-benzodioxane.

Starting from ethylpyrocatechine, a1lylpyrocatechine or propenylpyrocatechine, the reaction takes place in an analogous manner leading to products with quite similar properties.

Example 2 100 parts of 1-propyl-3z l-dihydroxybenzene, M. P. 55 C., B. P.o.2 mm. 111-112 0., are dissolved in 330 parts of 2n-caustic potash lye while 'acid (calculated 37.7 ccm.) it forms-readily soluble salts which are partially hydrolysed in solution. The hydrochloride melts at 102 C. under decomposition.

the 2-hydroxymethylpropylbenzodioxane so obi tained, B. P412 min. 142-143 C., are treated in 42 parts of pyridine with 56 parts'of thionylchloride thus giving 88 parts of the raw chlorine derivative. After purificationby distillation this product has a boiling point of l26-127 C. at a pressure of 0.2 mm.

66 parts of this chlorine compound are autoclaved at 140-150 C. for 10 hours with 51 parts of morpholine. The raw product sucked off from the precipitated morpholine hydrochloride is freed in sulfuric acid solution from the neutral substance still present, then, after reprecipitation, washed with caustic potash lye, dried, dissolved in ether and the hydrochloride precipitated by methyl-alcoholic hydrochloric acid. It forms snow-white, little crystals which are very easily soluble in Water; M. P. 224 C.

' The propyl-dihydroxybenzene is obtained by catalytic hydrogenation of isoeugenol into dihydro-iso-eugenol, B. P.13 mm. 124=-125 C., which is further demethylatedby means of hydrobromic acid.

Example 3 o-Vanilline dissolved in the equimolecular quantity of ,a normal base is converted by means of diluted hydrogen peroxide solution into the pyrogallol-l-methyl ether, B; P.13 mm. 133 C., M. P. 40 C. i

100 parts of this methyl ether are dissolved, in the absence of aerial oxygen, in 178 part of 4H1 caustic potash lye and shaken with 87 parts of epichlorhydrine. After a short time and under yield the chloromethyl derivative, 3. Ru

From this product there is obtained in yields of at least 90% the 2-morpholinylmethyl-omethoxybenzo-dioxane by heating the said prod.- uct for 10 hours at 1 40-150 C, with the double equimolecular quantity of morpholine, separat m he r e base nd uri in in theusua mannor h m tin 1 .9 2. the1. -.mor hol 5.1.1

When starting from the corresponding pyrogallol derivatives, e. g. pyrogallol-l-ethyl ether, there are obtained in the same manner the corresponding alkoxy-benzodioxanes.

Instead of the methoXy-pyrocatechine there may be used quite well pyrocatechine-o-carboxylic acid, protocatechuic acid or their methyl and ethyl esters.

Example -4 The 2-chloromethyl-o-methoxyebenzodioxane obtained as intermediate product according to Example 3 is heated in the autoclave for 8 hours to -130 C .with the same volume of tetraline and with an excess of diethylamine and the product isolated as above described. Thus there is obtained in a good yield 2-diethylaminomethyl-o-methoxybenzodioxane; B. P.o.5 mm. 142- C. 1 g. consumes 40.0 com. of n/10 acid; calculated 39.8 com The base gives .very hygroscopic salts with the usual mineral acids and carboxylic acids.

By replacing diethylamine by another secondary amine, such as piperidine, tetrahydroquinoline or -iso.-quino1ine and working under the same reaction conditions, the corresponding 2 alkylaminomethyl o methoxy benzodioxane derivatives are formed,

Example 5 100 parts of 2-chloromethy1-o-methoxybenzo- I dioxane areheated in the autoclave for 8 hours to -140 C. with 75' parts of n-butylamine. Then the reaction product is separated from the butylamine hydrochloride by washing the same and purified over the sulfate, whereupon the base is t free and purified by distillation. Thus no parts, i. e. 94% of the theory of 2-,-butylami no=- methyl:o-methoxy-benzodioxane are obtained in Ewm e .6

10 parts of the hydrochloride prepared according to Example '5 are used and the base is set free and dissolved in benzene. The dried solution is treated with 4.6 parts of finely powdered calcinated sodium carbonate, heated to 50 C. and then, while stirring, 4.6 parts of 'deacidifie d dimethylsulfate are allowed to slowly drop thereinto, while the temperature isg'radually increased to 60 C. Stirring is continued for a further hour at '70-80 C., the mixture is allowed to cool down, stirred with about 10 parts ofwater and n iatiqnandhur catiomby dis.-

a a sped-e11 tillation 9 parts of thetertiary base of the foracid, calculated 37.7 ccm. Contrarily to the salts of the secondary base the salts of the tertiary base are extremely hygroscopicI i By the same treatment of the secondary base with diethylsulfate there is obtained the corre sponding ethylbutylamino compound.

v Example 7 100 parts of 2:3-dihydroxynaphthalene are dissolved in 41 parts .of potassium hydroxide and 250 parts of water, treated with 78 parts of epichlorhydrine and shaken for 20 hours. The solid raw product thus precipitated is purified by digesting the same first with hot water, then with a diluted basekand finally again with water until the color reaction with ferric chloride has disappeared. It is now dissolved in benzene, dried and" recrystallised. Thus the '2-hydroxymethylnaphthodioxanel is obtained in form of pure white crystals; M. P. 162 hydroxyl number 258 (cal- L culated 259).

Fortheconversion the chlorine compound 30 parts of thisproduct aredissolved in 45 parts of pyridine and treated with16.5 partsof thionylchloridawhereupon, by theusual working up, there are obtained 28 parts/i. e. 86% of the theory of the chlorine compound in form of white crystals having amelting point of 68 C.

25 parts of the chlorine compound are heated for 3 10 hours to 150; C. with 18 parts of mor-' pholine. The solid reaction product is dissolved .on thewater-bathin 200 parts of n-hydrochloric acid; .;then the hydrochloride which crystallises out on cooling is separated, purified by recrystallisation from hot water and finally the base g is precipitated from the cold solution and crysta'llise'd" from "methanol. The 2-morpholinylmethylnaphthodioxane so-obtained witha yield of 70-80% shows the melting point of 116 C. (l

g. consumes 35.6 ccm. of n/10 acid, calculated 35.1 ccm.); its hydrochloride melts at 240C.

Like 2:3-dihydroxynaphthalene, other o-dihy- Example 8 2-hydroxymethylnaphthodioxane produced according to Example '7 is dissolved in about the tenfold quantity of alcohol and. this solution, after the addition of 2% of Raney-nickel, is treated at 120 C. under a pressure of 100 atmospheres with hydrogen, whereby for 100 g. of the substance about 202 litres of hydrogen are absorbed (for the absorption of 2 molecules of the substance the calculated luantity of hydrogen amounts to 208.3 litres). Now the alcohol is expelled from the reaction solution which was purified by means of silicagel. The 2-hydroxymethyl-tetrahydronaphthobenzodioxane remains as a highly viscous mass which crystalises out after a longer standing. -By the interchange of the hydroxyl group by a chlorine atom taking place, as usual, by means of thionylchloride and pyridine there results with a good yield the chlorine derivative, B. P.o.22 inm. 142-143 C., M. P. 61 C. This compound is autoclaved for 10 hours at 140-150 C. with about thesame quantity by weight of morpholine and with some drops of water, then the base is, as usual, isolated and converted by stirring in the heat with 2n-hydrochloric acid into the 2-morpholinylmethyltetrahydronaphthodioxane hydrochloride which is obtained with ayield of of the theory. Meltingpoint (under swelling up) 265 C. Hydrochloric acid content 10.9%, calculated 11.0%.

, Example 9 2-morpholinylmethyl-o methoxybenzodioxane,

made according to Example 3, is maintained at the boiling under reflux with the double quantity of 45 per cent by weight-of hydrobromic acid,

crystallised from water) is 274275 0., there is obtainedwith a good yieldby means of dicarbonate the free amino phenol of the formula white crystalsj P. 847-85 0., soluble in acids and bases. i

V The preparation of the compound from pyrogallolfand epichlorhydrin'e by reaction. in analkalinesolution, changing the alcoholic hydroxyl group in the resulting hydroxymethylhydroxybenzodioxaneinto chlorine and then replacing the chlorine atom by the morpholine radical ofiers no advantage, but requires by far much more, precautionary ,measures.

/ Example 10 43 parts ofmorpholine dissolved in 200 com. methanolare treated with 45 parts of a 29% formaldehyde solution. The solution is allowed to stand until the odor of the aldehyde has nearly disappeared, so that the formation of hydroxymethylmorpholine .has practically com- .pleted. Now 55 parts of pyrocatechine are added thereto in the absence of air, the mixture is allowed to stand for one day, heated for 4 hours to C. in a closed vessel and finally the methanol is distilled off. To the remaining aqueous solution of. morpholinylmethyldihydroxybenzene there are added, in the absence of air 31.5 parts of potassium hydroxide dissolved in parts of. water and then 70 parts of epichlorhydrine. The solution being initially brownish-black brightens on shaking and the resulting benzodioxane compound is partly precipitated in a crystalline form. It is separated.

from the solution which is then extracted. The

I collected raw product is now dissolved in diluted hydroxymethyl-ar-morpholinylmethyl benzodioxane (ar-substituted in the aromatic nucleus) Boiling is continued ungxa ne, h -{ade according to v. lil xa mple' 9, is inter,-

' hydrochloride is a white erystal meal which is if} meme;

Mitheee s ille pe elwsm e elsqseine 2 mg:

a product of the fqrmula O h Zhidiekiimth homhqli can le i CHam "CHTCHFOH tuse vwithsi a ie ep :h xme b ldim illy H1 am ne Q hmmxmei il m sm n h gEaqampZe 1 1 mm w th a eti a d f ll d ids in t rati i 2:1 and this solution first heated for several ,'.CH QH, N l hours up to about 1-00 Ce'and then, after the onrci v dditien eanhy lrid r-st l ;hqated..1 zs m im K itotb 1m h etiwpe dles e QQQQiQQflH" removed under :re/(mqed p e s sul e, is formed, wherein the ,puelear methyl group imie leraleciit e o ut e ,.purifleckb sh kin pu b ;t;he,s a me ,with en prganic sqlv ent and madegl- 20 2. The 'ben'zo-dioxane derivatives of ltheegena nei t e cold. The ':mq hQ. in 1m thy m1 formula v o-acetoxybenzodioxanethus precipitated is colo .CHz-CH:

e1ine-so1utienbygaeid fi atie tandz reqi it t qn wit z ca bonat "T e met-wider ati l o ms o a-iviscous, i h yellowzliquid; t is s inso1ub rm col .bases, but so uble ton he t n u de sano fic iio It 1 s as l e clearly solubl n acids. :1 we. cons mes orithe-n ut nal satmn 34.0 ccm. .of 1 /10 acid, calculated 34.1 com. The

easily soluble in water '(cont'rarily tojhe hydrochloride-of :the phenol Joese) angi melts at f fh s aim re nt e 2 el a e i :e .@e. 2 CH r h A A h 2 presently-preferred prbcess and'products;

1. Process for the menuf a eture pf methyl Q substitution j deriyatives ,Qf 2-me thylbenzodio xane E40 ,Whe'i eifi-GH is situated in -o-posi-tion to ohe 10! ic comp i ,s nd n ng h lis ic lkalin h XE "b ihg- C Q F F W' medium prthe methylpyrodatechine pfjthe fprlessneon lppunds of valu able therapeutic prop er- ,mula. mm. pressure forming' watehsblublesaltswith acids j'a ic'l pessessir g valuabletherapeutic progr- L 19 I I 1 =feina ining l aw prpqget,is dissolved.in gilute stands in qrtho positien to'one of the oggggen. 

